1. Field of the Invention
One or more embodiments of the present invention generally relate to a network environment, and more particularly, to a method and apparatus for synchronizing the real time clocks of nodes within the network environment.
2. Description of the Related Art
A network environment, such as a distributed system, commonly includes an arrangement of nodes which are interconnected via a communication network. Each node of the network environment may include a local clock which maintains a local time for the node. It is commonly desirable to maintain a common sense of time in a network environment by synchronizing the local times maintained in the local clocks of its nodes.
One prior protocol for synchronizing the local clocks of a network environment is the Network Time Protocol (NTP). Typically, a node operating according to NTP periodically generates a packet containing a time value obtained from its local clock and transfers the packet via the communication network. Nodes running NTP usually gather these packets from the communication network and perform statistical analysis of the obtained time data and in response adjust the time values in their local clocks.
Each node may include a switch for channeling a packet from an input port to an output port that will forward the packet to its intended destination. The time the switch takes to transfer the packet from the input port to the output port may vary, depending on the packet and other factors. This variation in packet transfer time through the switch may be referred to as latency, which may cause jitter. Unfortunately, the jitter introduced by the switch often limits synchronization of the local clocks within the nodes.
Accordingly, a need exists in the art for a method and apparatus for synchronizing the local clocks of a network environment.